This invention relates to apparatus for cleaning teeth with the effectiveness of dental floss, and more particularly to cleaning the parts of the teeth under bridges and braces where dental floss cannot easily reach, and from where an ordinary floss cannot efficiently remove unwanted deposits.
It has long been known that dental floss is one of the most effective means for cleaning interdental surfaces. Dental floss sliding laterally across the surface of a tooth scrapes away unwanted deposits with great effectiveness. For most natural teeth, where the surfaces to be cleaned can be reached by laterally sliding in a length of dental floss, cleaning can easily be accomplished with dental-floss applicators such as described in U.S. Pat. No. 4,214,598 invented by the inventor of the present invention. Such flossers are approved by the American Dental Association.
However, the above-mentioned flosser cannot reach under bridges and braces. Furthermore, even when an ordinary length of floss has been inserted into the areas under a bridge or a brace, the floss cannot be removed laterally, it has to be pulled out longitudinally. So the floss cannot scrape away unwanted deposits (or dirt) effectively.
Several devices exist for cleaning areas under bridges and braces:
Small brushes are made for cleaning such areas; but these brushes are too stiff to conform to/the curvature of the tooth surface; they have metal stems that hurt the gingiva; they are difficult to clean; and they are too expensive to be thrown away after only one use.
Threading devices are commonly used for threading floss into the difficult-to-reach areas behind bridges and braces, but these threading devices are clumsy to use. Furthermore, floss is not an effective cleaner even when inserted into the areas under bridges and braces because the floss cannot slide out laterally under tension; dirt cannot be effectively scraped out of the enclosed area, instead, the dirt ends up being pushed from one side to another without really being removed.
U.S. Pat. Nos. 4,142,538, 4,008,727, 3,896,824, and 3,837,351 describe flosses which are fabricated into three sections: In the center section, the floss is deliberately made fluffy to act as a sponge for wiping away the dirt. The two end sections are made thin and stiff to facilitate insertion into areas under bridges and braces. However, these flosses are also not entirely satisfactory because: 1) under tension, the enlarged center parts of these flosses stretch out easily and become much smaller in crosssection and are therefore less effective as dirt-remover. 2) They are not stiff enough to provide any effective scraping action for dirt removal. 3) Sometimes the strands get tangled up, or become entangled with solid dirt, then they cannot be pulled out of the interdental area.
U.S. Pat. No. 4,832,063 describes a cleaning device with a threading leader attached to a braided cord which provides a textured surface for removal of unwanted deposits. Such braided cord sections cannot be compressed easily into a small crosssection, so the device is not suitable for use between closely-spaced teeth; furthermore, the cord becomes saturated with dirt and is then ineffective as a scrubbing surface.